The Quay Crane Deployment Problem At A Maritime Container Terminal

Abstract

Container unloading/loading at marine container terminals (MCTs) is a key logistic process, to which some research efforts have been addressed by using mathematical programming models formulated in a deterministic-static environment. Vice versa, DES models in a stochastic-dynamic environment are well capable of representing the entire process. Hence, simulation results to be an effective planning and control tool for decision making at all decisional levels. Here we remark that optimal decisions in MCTs may be practically pursued by modelling the whole MCT and focusing attention on the core logistic processes, while representing in a simplified manner the remainder. We focus on the operational management of the cranes deployed along the quay, during the container unloading/loading process at a given number of vessels according to a previously planned berthschedule. We suggest a two-phase approach to the quay crane deployment problem: in the first phase an IP model is used to decide when and how many cranes must be assigned to each vessel; afterwards, we propose a heuristics to determine which specific crane should be assigned to a vessel. We indicate how this approach can be successfully integrated in a DES model, already available, to support dynamic assignment of cranes to berthed vessels.

Modeling, simulation and optimization in logistics

“…Most terminals use the weekly plan to produce a daily crane assignment on a 48-hour time-horizon. Hence the author proposes a standalone method for the allocation of QCs by taking as input the weekly plan (Legato et al 2008b). The proposed method was developed for QCs travelling on track and therefore non-crossing constraints have been accounted.…”

Combined quay crane assignment and quay crane scheduling with crane inter-vessel movement and non-interference constraints

“…(Yang et al, 2012) suggested to deal with BACAP by solving simultaneously BAP and QCAP. They formulated a mathematical model which integrates the BAP constraints of (Guan and Cheung, 2004) and the QCAP constraints of (Legato et al, 2008). The objective function for this model is the combination of the objective functions of the BAP and QCAP models.…”

“…BACAP is the problem of allocating berthing times and berthing positions to vessels and, at the same time, determining the optimum number of quay cranes to service them. (Legato et al, 2008), addressed QCAP with a predetermined berth position and time following the solution of BAP. They assumed that quay cranes could not move between vessels before all tasks are performed and the vessels processing is completely finished.…”

Simulation At A Maritime Container Terminal: Models And Computational Frameworks

“…Assuming that the berth schedule is deterministic for the model, in the first phase we use CPLEX to solve a mathematical model that is able to assign for every vessel at each one-hour time-slot a sub-set of RMGs (Legato et al 2008a). Afterwards, in the second phase we use a metaheuristics to schedule the ship holds to the assigned RMGs (Legato et al 2008b).…”